1. Field of the Invention
The present invention relates to a seat for use in a vehicle such as an automobile and, more particularly, to an improved vehicle seat which comprises a cushion member formed of a foam material, a top member covering the cushion member, and a hang-in member for hanging the upper surface of the top member into the bottom portion of the cushion or hanger member.
2. Description of the Prior Art
FIG. 1 illustrates a conventional seat (A") of this type. In this figure, reference character (a") designates a cushion member formed of foam material such as urethane foam. The cushion member (a") comprises a central portion (10), and two raised side portions (11) (11) located around the central portion (10) and foamed integrally with the central portion (10). There are formed through-bores for insertion of hang-in members (2") extending vertically along boundary lines between the central portion (10) and side portions (11) (11) at a predetermined interval. Character (b") represents a top member for covering the cushion or hanger member (a"). Onto the rear surface side of the top member (b") are sewn the ends of the hanger members (2")(2") such as hanging strings to be inserted through the through-bores of the cushion member (a").
When an occupant is seated on this seat (A"), the seat (A") is caused to deform in the manner as shown in FIG. 1. In other words, if a load is applied to the central portion (10) of the cushion member (a"), then the central portion (10) is bent downwardly, which downward bending in turn causes the side portions (11) (11) of the cushion member (a") to rise up from their original positions as shown by two-dot chained lines to such positions as shown by solid lines.
Accordingly, as shown in FIG. 1, since the side portions, when raised up, are brought into contact with the buttocks of the occupant, such conventional seat gives the occupant an uncomfortable feeling. Also, because the side portions of the cushion member are displaced whenever the occupant is seated, such side portions tend to get weak-kneed or will not be able to retain their shapes. As a result of this, there are produced wrinkles in the top member which covers such weakened cushion member side portions, which wrinkles deteriorate the aesthetic appearance of the seat.
To avoid the drawbacks mentioned above, there is proposed a seat in which the central portion and side portions of a cushion member are respectively formed of separate foam materials, that is, in which the side portions of the cushion member are formed of harder urethane foam over the central portion thereof. The newly proposed seat, however, is disadvantageous in that it can not be easily manufactured by using a mold.